ASTM D5384 Standard Test Methods for Chlorine in Used Petroleum Products (Field Test Kit Method)
5. Apparatus
5.1 Both the fixed end point test (Method A) and the quantitative test (Method B) are available as completely self-contained test kits containing all the reagents necessary to complete the test.3 Each kit includes a sampling syringe to withdraw a fixed volume of sample for analysis; a first polyethylene test tube into which the sample is introduced for dilution and reaction with metallic sodium; a second polyethylene tube containing a buffered aqueous extractant, the mercuric nitrate titrant (Method A only), and diphenyl carbazone indicator; a polypropylene filter funnel; and a 1- mL titration syringe filled with mercuric nitrate titrant (Method B only).
5.2 If prepackaged kits are not used, the following materials and reagents will be required.
5.2.1 Test Tubes, two test tubes capable of holding 30 mL, sealed with screw caps.
5.2.2 Filtration Device, composed of a funnel containing a plug of polypropylene felt (or equivalent) to retain residual hydrocarbons from 5 mL of aqueous solution.
5.2.3 For quantitative Method B only, a 1.0-mL polypropylene tuberculin type syringe or equivalent. The syringe is to be marked with divisions at every 0.025 mL.
6. Reagents
6.1 If prepackaged kits are to be used, all necessary reagents and instructions are contained within the kits.
6.2 If not using prepackaged kits, the following must be prepared.
6.2.1 A solution of 10 % (m/m) naphthalene in bis-2-methoxy-ethyl ether (diglyme). Dissolve 10 g of naphthalene into 90 g of bis-2-methoxy-ethyl ether.
6.2.2 A dispersion of 40 % (m/m) ground sodium in mineral oil.
6.2.3 A 0.15 % (mass/volume) solution of s-diphenyl carbazone in ethyl alcohol. Dissolve 0.15 g s-diphenyl carbazone powder into 100 mL of ethyl alcohol.
6.2.4 For Method A, a 4.75-mmol/L solution of mercuric nitrate. Prepare a mercuric nitrate stock solution by first dissolving 5.14gHg(NO3)2•H 2 O(WARNING - EXTREMELY TOXIC) in 5 mL of 50 % (vol/vol) nitric acid. After solute has completely dissolved, make up to 150 mL with Type II water. Stock solution = 0.100 mol/L. Prepare 4.75 mmol/L solution by putting 47.5 mL of stock solution into a 1-L volumetric flask and make up to 1 L with Type II water.
6.2.5 For Method B, a 13.7-mmol/L solution of mercuric nitrate. Place 137 mL of stock solution (see 6.2.4) into a 1-L volumetric flask and make up to 1 L with Type II water.
6.2.6 An aqueous buffer solution containing 6 % (mass/mass) sodium sulfate, 2.6 % (mass/mass) sodium phosphate and 3.175 % (mass/mass) sulfuric acid (pH 1.5).
7. Sampling
7.1 Take samples in accordance with the instructions in Practice D4057.
7.2 Free water, as a second phase, is to be removed. However, this second phase can be analyzed separately for chloride content by using a method suitable for materials with high water content (Warning - The gray ampules contain metallic sodium which is a flammable, water-reactive solid. Reaction with water will generate flammable hydrogen gas.) (Warning - When the sodium ampule in either kit is crushed, oils that contain more than 25 % (m/m) water will cause the sample to turn clear to light gray and will build noticeable pressure. Under these circumstances, the results can be biased excessively low and should be disregarded.).
